In order to understand the molecular mechanisms of action of rhodopsin in the transduction of light into nerve impulses we shall attempt to incorporate rhodopsin into an artifically reconstituted lipid bilayer membrane (lbm). The basic strategy will consist of fusing the rhodopsin-containing membranes of the discs inside the rod outer segment of bovine retinae with preformed lbm. Subsequently we shall attempt to characterize any light-dependent, ion-specific conductance changes of the rhodopsin/lbm system by studying in detail the electro-optical properties of these. A more general objective is to characterize the conditions necessary for fusion of biomembranes with artificial lbm. By labeling rhodopsin with fluorescent probes we shall monitor the appearance of the fluorescent signal in the lbm. Other systems which will be utilized for the study of fusion are Acholeplasma laidlawic labelled with fluorescent lipids and artificial lipid bilayer vesicles made from fluorescently labeled phospholipids. BIBLIOGRAPHIC REFERENCES: Cohen, F.S., M. Eisenberg, and S. McLaughlin. 1977. "The Kinetic Mechanism of Action of an Uncoupler of Oxidative Phosphorylation". J. Membrane Biology, in press. Eisenberg, M., M.E. Kleinberg, and J.H. Shaper. 1977. "Channels in Black Lipid Membranes". Ann. N.Y. Acad. Sci. USA., in press.